Duplex revolving screen for cleaning and grading coal



(No Model.)

V I L. AULM'ANN. DUPLEX REVOLVING SCREEN EUR CLEANING AND GRADING GOAL.

Patented Feb. 6 1894.

U ITED STATES PATENT OFFICE.

LORENZ AULMANN, OF DES MOINES, IOW'A.

I DUPL EX REVOLVING SCREEN FOR CLEANING AND GRADING COAL.

SPECIFICATION forming part of Letters Patent No. 513,973, dated February6, 1894.

Application filed February 28, 1893. Serial No.64,049. (NomodeL) .Whichthe following is a specification.

My object is to facilitate the construction andimprovetheoperation ofrevolving screens as reqniredto advantageously clean and grade coal andlike solid substances. 1

My invention consists in heads speciallyadaptedforconnectingtwoconcentricscreens, and the combination ofscreens, a rotating shaft and a frame, as hereinafter set forth, pointedout in my claims, and illustrated in the accompanying drawings, inwhich- Figure 1 shows a longitudinal section; Fig. 2 a transversesection through the line was of of Fig. 1 looking toward the left andthe head or front end of the machine, and Fig. 3 is a side elevationshowing the screen mounted upon a frame as required for practical use.

A represents the head of the machine in the form of a cylindrical framecast complete in one piece. It has a hub B at its center, radial arms 0extending to its circular rim, D, that has an inwardly extending flangeD The hub has an angular bore adapted to admit an angular shaft and therim has spurs f on its outer surface adapting it to serve as a sprocketwheel to impart rotary motion to the complete screen.

F is a rim, of larger diameter, integral wit the outer ends of the arms0, and in concentric position with the rim D.

A is a corresponding head formed complete in one piece, but has noflange projecting inward from the rim, and no spur on the periphery ofthe rim.

A is a frame corresponding in diameter with the rimsD of the frames orheads A and A*.

H is an angular shaft extended through the hubs of the three frames A,A, and A and fastened thereto. It hasjournals H on its ends.

No. 1 is a Wire screen clamped to the outside surface and inner portionof the rim D of the head A and the periphery of the rim of the frame Aand the frame A by means of rings J and screw bolts passed through theoverlapping parts and nuts on the inner ends of the bolts.

No. 2 is a Wire screen fixed to the rim F of the head A, by means of aring J and screw bolts and nuts, and to the frame A by means of a ring J3 and screw threaded bolts K that extend from the rim of the frame A asshownin Fig. 1.

No. 3 is a screen coarser than screen No. 2 fixed to the rim of theframe A by means of the ring J 3 on the bolt is and to the rim F of theframe A by means of a ring J 4 and screw bolts and nuts. A duplex screenis thus produced adapted to facilitate the cleaning and grading of coaland other substances.

L represents a stationary chute through which coal can be readilyintroduced into the cylinder when it is mounted in an inclined positionas shown in Fig. 3. I

M is a drive chain on the spurs f of the rim D and connected withgearing adapted to actuate the chain as required to rotate the div plexscreen in an inclined position.

To operate the machine I put it in motion and then throw broken coalinto the chute L to allow it to descend therefrom into and through thescreen by gravitation. The small particles of dirt or clay and coal willimmediately fall through meshes of the No. 1 screen and larger pieces ofcoal will descend thereon while the smaller portions will pass throughthe meshes and the larger pieces drop out from the lower end of the N0.1 screen. The

dust and dirt that fall from the screen No. 1,

upon the concentric screen No. 2 will fall through while small particlesof coal will descend thereon to screen No. 3 and fall through its meshesand the smaller pieces of coal that fall through the screen N0. 1 intothe screen N0. 3 will also drop through the meshes of the N0. 3 screenwhile the larger pieces pass out from its lower end. The refuse or wastemat ter will thus be deposited under the screen No. 2, the nut coalunder the screen No. 3 and the largest pieces of coal at the lower endof the machine.

The length and diameter and numbers of screens may vary as required toproduce machines differing in capacity, and the meshes of the screensmay also vary in size as required for cleaning and separating or grading coal and other substances.

e that has a rim D and a flange It is obvious that by means of the headA D and spurs f on the periphery of the rim and a concentric rim 0 oflarger diameter and a hub and arms or spokes, all cast complete in onepiece, the construction of the machine is greatly facilitated by meansof this single improved element, and the operation of the completemachine improved by the means thus provided for applying power direct tothe head by means of a drive chain.

I claim as my invention- 1. A frame or head for a duplex rotatingscreen, comprising a bored hub adapted to admit a shaft, radial armsprojecting from the hub, a rim near the outer ends of the arms havingspurs on its periphery to engage a drive chain, and flange extendinginward to partially close the head, and a rim at the ex tremities of thearms, for the purposes stated.

2. An improved duplex screen, for cleaning and grading coal, comprisinga head having a bored hub adapted to admit a rotating shaft and armsextending radially from the hub and provided with a Tim on their endsadapted to fix the end of a cylindrical screen thereto,

and also adapted to serve as a drive Wheel, and a flange extendinginward from said rim to partially close the head, short arms projectingradially from said rim and provided with an auxiliary concentric rimadapted for fixing the end of a cylindrical screen thereto, a circularframe having a bored hub and radial arms and two concentric rims adaptedfor fixing the ends of two concentric cylindrical screens thereto, acorresponding circular frame having a bored hub and radial arms andconcentric rims fixed to the central portion of the concentric screens,two concentric screens, a rotating shaft extending through the hubs andfastened thereto to rotate them, a frame adapted to support the shaft inan inclined position, a chute for conveying the coal into the head orthe inner cylindrical screen, and means for transmitting motion to theflange or drivewheel of the head as required to actuate the machine inthe manner setforth for the ptirposesstat-ed;

LORENZ AULMANN. Witnesses:

J. RALPH ORWIG, THOMAS G. ORWIG.

